[Page 1072]Developmental norms are characteristics, dispositions, capabilities, and/or behaviors that are typical of people at each age (henceforth described simply as “characteristics”). They refer to the central tendencies of each age cohort. They are relevant to many domains of psychology (e.g., educational and clinical) because they provide benchmarks of typical behavior as well as standards against which positive and negative deviations are measured. This entry provides an overview of what developmental norms are, how they are established, why they are important, and some of the factors that influence them.